Matter that can be classified as two ways
formula for density
D=m/v
3 science tools to find volume
graduated cylinder, beaker and a ruler
when an object decreases in volume what would the density do?
increase
describe the motion of particles in a solid, liquid and gas object.
solid is slow, liquid is medium and gas is fast.
the phases of water form in order, from the phase with the slowest molecular movement to the phase with the fastest molecular movement.
solid, liquid and gas
potential energy
stored energy that comes from position
mixture
substance that contains morethan one kind of matter and is not chemically combined.
compound
substances made of two or more elements that cannot be seperated by physical means.
element
substances that contain only on kind of matter
why does the tempature change very little when an object is undergoing a change in state even though energy is applied continuosly?
the atoms in the material change shape for the tempature to rise.
atomis mass
the average mass of all the known isotopes of an element
menucus
the curved surface of a liquid when it is a tube and it can curve up or down
valence electrons
the electrons in an atom that are involved in the formation of chemical bonds.
strong nuclear force
the force that holdsprotons together when they are very close together.
What happens to the h2o molecules when an ice cube melts?
the heat is used to overcome the forces holding molecules together in the solid rather than increase the tempature.
When you freeze water, what happens to energy and number of molecules?
the numbers of moleculs will always stay the sam and the energy slows.
what causes protons to repel?
when they are both positive
how many electrons and protons are present if a fluoride ion has a charge of -1? flurine's atomic number is 9
10 electrons and 9 protons
The proton is one kind of particle that makes up the atom and carries a ________ charge.
Positive
chemical change
a change in a substance that involves the breaking and inferring of chemical bonds to make a new substance or substances
mass
a measure of the inertia of an object the amount of matter an object has.
homogeneous
a mixture in which every sample of it has the same composition such as milk.
heterogeneous mixture
a mixture in which every sample of it might have a different composition such as chicken noodle soup.
substance
a mixture that connot be separated into different kinds of matter using physical means.
nuclear fission
a nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energy
ion
an atom molecule that has either gained or lost electrons
physical change
change in the physical properties of a substance
power plants convert chemical energy, mechanical energy and heat into _______ energy
electral
an atom contains ______ in various energy levels.
electrons
the law of conservation of energy states
energy may niether be granted or destroyed, the sum of all energies in the system is constant.
kinetic energy
energy that comes from motion
compare the amount of energy necessary to heat a substance to the amount of energy needed when the substance is cooled to the original tempature.
it takes less energy to warm it because the kinetic energy is bigger, when the amount of heat grows.
The third kind of particle carries a negative charge and has almost no _____
mass
Matter that can be classified as two ways
mixtures and substances
neon has 10 electrons and 10 protons. WOuld an atom that has 9 electrons ad 10 protons be the same type of element? explain your answer
neon is neutral an atom with 9 electrons and 10 protons would be considered an ion
The nuetron makes up for "missing mass" and is found in the _________
nucleus
in an atom what particle does the proton repel?
proton
volume
the space that a substance ocupies or contains.
thermal energy
the sum of all the kinetic energy of a material's atoms and molecules.
the noble gases such as helium and xenon are non reactive why?
they have completely filled outer valance electrons
elements in the same column on the periodic table have similar chemical reactivity because why?
they have the sam amount of valance electrons
Compare and constrast a kilogram of feathers and a kilogram of bricks
they have the same mass different volume.
At a constant tempature and pressure, liquids retain what?
volume